GTX680: Both DVI's after 10.9.3? (Plus 2600XT woes)

I just upgraded to 10.10 GM Candidate after holding out on 10.8 for the duration of the Mavericks release. I found two issues after doing so.

The upper DVI port doesn't work on my 4 GB GTX680 in 10.10 (and apparently stopped working for everyone else in 10.9.3).

My ATI HD 2600 XT card is useless in 10.10 because of a graphical corruption bug that's affecting both Mac Pros and all three of these cards that I own.

This has got me in a really tight bind because at home I only have two usable LCDs now out of the SIX outputs the machine has (I have the goodies to connect only my 30" and an analog LCD to the GTX680's working outputs) and at work I only have one usable output (because I have two CRTs there and the 5870 only has one DVI-I, the 2600XT being in-op). I've always kept the 2600 XT cards "just in case" a update broke the GTX but never really anticipated all three 2600 XTs AND the GTX becoming hobbled at the same time.

I've finally had to upgrade so I can run Xcode 6 so reverting back to 10.8 isn't an option. I could revert to 10.9 but I really dislike that release and it won't fix my GTX issue anyway. Does anyone know of a way I can restore the second DVI output to my EVGA 4GB GTX680 card? I have tried the OEM PC ROM (which lost me the boot screens but gained me nothing). The 4 GB EFI ROM that was posted around here a few years ago is what I have been using. I've also tried various driver hacks to no avail. The only solution I can find that should actually work is sending my card to MacVidCards to be flashed as they seem to have found the problem, but that involves having NO usable outputs on my main machine for some period of time. Plus I'm itching to bump up to a GTX980 when its more reasonable and I'd hate to put any more money into the GTX680 setup.

I had no luck with the upper DVI after reverting to the shipping firmware, which confused me as well as I thought the issue that broke the upper DVI port resulted form the ROM I had flashed (which came from this thread). I flashed it back to the ROM in that thread now, as I believe that's also necessary to get 5.0 GT/sec speeds on my MacPro 3,1 (unless that has changed).

I did find a DisplayPort cable and was able to hook my secondary display up to the DisplayPort instead of the Upper DVI port. Now I'm in much less of a bind as I have two working displays.

I previously had five displays on the machine. Four are on my desk. They were connected to the GTX 680's two DVI ports, its DisplayPort through a DP > MDP > VGA adaptor chain, and the last panel was on the 2600XT through DVI > VGA. Next to my audio rig I have another display connected to the GTX680's HDMI port through a 25 foot cable, and I use SwitchRes X to switch between that one screen and the four on my desk when I move back and forth.

I have now put my two main displays on the GTX680 via the lower DVI and DisplayPort, retained the HDMI setup, but moved the second small analog LCD to the 2600 XT. The two displays on the 2600 XT work for Terminal and a few other limited cases but even BBEdit was experiencing graphical corruption after a few minutes of use.

At work I am struggling with the 2600 XT as well because I run two huge CRTs and I can't get analog refresh rates worth a flip through a MDP adaptor so I have to use the one DVI-I on my 5870 and one DVI-I from the 2600 XT, so I have one "good" display and one that's only good for Terminal.

If you think the PC BIOS should restore the second DVI I will give it a second try when I get home later tonight. I may have gotten confused and had the wrong cables hooked up when I tried it before, as there are dozens of now-unused cables floating around that I have yet to rip out back there. I appreciate your reply!

Regards,
Ryan

Edit: One aside about the stock ROM: I did adjust the clock speeds down when I flashed it, because I found a year or so ago that with the raised clock speeds on the FTW+ card, (I know this is silly, but still) the "Blobs" filter option in Minecraft would cause the machine to instantly power off if activated due to the card drawing too much juice. Adjusting the clock speeds down to the normal GTX 680 levels fixed that problem for me so I also adjusted them down when refreshing the PC ROM. I suppose that modifying that ROM through the software from the above-linked thread could have also screwed up the upper DVI? I will try an unmodified flash of the EVGA ROM tonight, for science.

MacVidCards, you are of course, correct. I retried the PC ROM and it works with the upper DVI port, even after modifying the clock rates and power levels to a stock GTX 680 spec. I'm not sure what I did wrong the first time that caused it not to work but something may have been disconnected.

I haven't been able to determine if I'm getting 5 GT/sec rates on the card yet but for now I can get work done on the machine and I'm happy for that! Thanks!

MacRumors attracts a broad audience
of both consumers and professionals interested in
the latest technologies and products. We also boast an active community focused on
purchasing decisions and technical aspects of the iPhone, iPod, iPad, and Mac platforms.